This proposal requests support for a P-50 Center award, extending over a five-year period and building on Rand's existing program of population studies. Support is requested for: (1) an administrative core, (2) a data Management/Processing and Statistical Services Core, (3) a research dissemination core, and (4) a program of seven research projects having two distinct foci ("Demography of Families and Households" and "Recomposition of Regional and Local Populations"). The research program emphasizes three strengths of Rand's population studies: (1) application of demographic analysis to issues of public policy, (2) the use of large-scale, longitudinal data sets to conduct analyses at the individual and household levels, and (3) the analyses of population change at regional and local scales. The proposed center will: widen the range of topics examined; make possible major economies of scale in analyzing several large data sets; lend continuity to the demographic research conducted at Rand; and establish a continuing focus (likely to last well beyond the award period) on topics NICHD has chosen for emphasis.